John green



J. GREEN. LIFTING JACK.

(No Model.)

No. 462,796. Patented Nov. 10,1891.

Nrrnn S'ra'rns PATENT OFFICE.

.IOIIN GREEN, OF RENOVO, PENNSYLVANIA, ASSIGNOR OF ONE-I'IALF TO JOHN \VARD AND JAMES H. SHEDDY, OF SAME PLACE.

LlFTlNG-JACK.

SIPECIFICATION forming part of Letters Patent No. 462,796, dated November 10, 1891.

Application filed September 18, 1891. Serial No. 06,122- (No model.)

To all whom, it may concern:

Be itknown that I, JOHN GREEN, a citizen of the United States, residing at Renovo, in the county of Clinton and State of Pennsyl- Vania, have invented certain new and useful Improvements in Lifting-Jacks; and I do hereby declare the following to be afull, clear, and exact description of thein vention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to lifting-jacks, and has for its object certain improvements in construction,which will be hereinafter fully disclosed in the following specification and claims.

In the accompanying drawings, which form part of this specification,Figure 1 represents a side view; Fig. 2, avertical section; Fig. 3, a perspective of the head of the rack-bar; Fig. 4, a side view of the web of the frame, and Fig. 5 an end view of the same.

Reference being had to the drawings and the letters thereon, A indicates the frame or body of the lifting-jack, which is provided with base a, a central web I), which is mortised in the base a, as shown in Figs. 2 and 4, and sides c c, secured to the web I) by bolts or rivets d, the whole being preferably made of hard wood to produce a very cheap, light, and yet a strong and serviceable implement. It is obvious, however, that the body may be made of cast-iron, or the web and base may be cast-iron and the sides of rolled plate.

lVithin the body A is a Vertical slot 6 to receive a rack-bar B, and a pocket f to receive a pinion O and one end of an operating-lever D. The outer end 9 of the lever is preferably made of wood, and to its front end are attached metal plates or extensions 7L h, between which the pinion O is supported upon a pin or bolt 2', which passes through the sides 0 0, plates h h, and the pinion and forms a fulcrum for the lever D. Between the plates h h is pivotally secured a pawl or latch is by a pin Z, and which engages the pinion 0 below its axis, is operated by its handle or extension m, and held in operative contact with the pinion by. a spring a, secured to the end of the lever D. Above the pinion in the pocket fis pivotally secured another pawl or latch 0 by a pin 1), and which engages by gravity with the pinion C above its axis. The pawls or latches engaging with the pinion lock the jack effectually and are in position for ready and easymanipulation in lowering bodies. In the act of raising a body the pawls both engage automatically with the pinion; but in lowering abody the lever D is moved to its lowest position,wi-th the pawl 70 in engagement with the pinion, the pawl 0 is disengaged from the pinion, and the lever raised, which will permit the rack-bar to descend while the lever is ascending. lVhen the lever has reached its highest point, the pawl 0 is put in engagement with the pinion, the pawl 79 releasethand the lever D lowered and its pawl 7.; allowed to again engage the pinion, when the foregoing operation is repeated until the body has been lowered to any desired position.

E indicates a detachable hook, the vertical arm q of which is provided with perforations r, and upon which is adjustably secured a jaw s by a pin 25, which passes through holes in the lugs u on the inner end of the jaw and the perforations a" in the arm q of the hook.

The lifting-jack is especially designed for railroad use and the hook adapted to engage a rail on a track or bridge-timbers to be raised fromthe ground or trestle-work, but is applicable to general use. Vhen used upon painted work, a non-metallic pad o,of wood or other suitable material, is interposed between the head 10 of the rack-bar and the object to be operated upon. The pad may be held in place on the head 10 by pins or other suitable devices, which it is not considered necessary to illustrate.

Having thus fully described my invention, what I claim is- 1. In a lifting-jack, the combination of a rack bar, a lever, a pinion attached thereto and engaging said rack-bar, and pawls engaging the pinion above and below its axis, one of said pawls being supported by the lever and the other by the frame of the jack.

2. In a lifting-jack, the combination of a rack-bar, a lever, a pinion attached thereto and engaging the rack-bar, a pawl pivotally secured to the lever and held in engagement rack-bar, a lever having metallic extensions on its inner end, a pinion between saidextensions and engaging said rack-bar, a springactuated pawl pivotally secured between the extensions, and a gravity-pawi pivotally secured to the frame of the jack and engaging the pinion above its axis.

In testimony whereof I affix my signature 1n presence of two witnesses.

JOHN GREEN. Witnesses:

D. C. REINOHL, W. PARKER REINoHL. 

